Sma 50 crosses BB

Algos, strategies, code
1

Sir Kindly provide me code for Buy when sma 50 crossing the Bollinger band lower band upwards. And sell when sma 50 crosses over the Bollinger band upper band downwards. Highly appreciate quick response

2

For the above given condition

Buy Script

CROSSOVER(SMA(CLOSE,50),BBB(CLOSE, 20, 2, EXPONENTIAL))

Sell Script

CROSSOVER(SMA(CLOSE,50),BBT(CLOSE, 20, 2, EXPONENTIAL))